So called resolvers are used in order to determine the angular position of two links of a machine which can be rotated in relation to one another with respect to an axis of rotation. One example of a machine with a link that can be rotated in relation to itself is a robot. Robots in general are handling machines which are equipped for the automatic handling of objects with useful tools and are programmable in several axes of movement in particular with regard to orientation, position and work routine. Robots usually have a robotic arm with several links and programmable controllers (control devices) which control or regulate the movement sequences of the robotic arm during operation. The drives are e.g. electrical drives and the links are pivoted in relation to one another with respect to axes of rotation.
Resolvers are known to a person skilled in the art, e.g. from EP 2 211 148 A2. A resolver is defined as an electro-magnetic transmitter for conversion of the angular position of two components moved in relation to one another to electrical output signals. Two components moved in relation to one another are for example two links pivoted with respect to an axis of rotation or a rotor of a motor that rotates relative to the stator of the motor. The output signals are as a rule two sinusoidal electrical signals shifted by 90 degree phases, in particular two sinusoidal electrical voltages shifted by 90 degree phases, on the basis of which the angular position modulo n can be determined, wherein n is the so-called number of pole pairs of the resolver which arises from the arrangement of coil windings and is a small positive natural number, and can also be 1.